Automatic grindstone-dresser.



F. E. RILEY. AUTOMATIC GRINDSTONE DRESSER.

APPLICATION FILED MAR. 23| 1918.

INVENTOR A ITO/Mrs WITNESSES F. E. RILEY.

AUTOMATIC GRINDSTONE DRESSER.

APPLICATION FILED MAR. 23. I918.

A TTURNEVS FRED E. RILEY, OF LIVERMOBE.FALLS, M.

AUTOMATIC GRINDSTONE-DRESSFIR.

aaeaeea.

To all whom it may concern:

Be it known that I, FRED E. R-rmr, a. citizen of the United States, and a resident of Livermore Falls, in the county of Androscoggin and State of Maine, have invented a new and Improved Automatic Grindstone-Dresser, of which the following is a full, clear, and exact description.

This invention relates to power operated tools and has particular reference to devices for dressing or truing the curved surfaces of large grindstones, such for instance as are used in the manufacture of pulp for paper in which operation blocks of wood are subjected under heavy pressure to the abrading action of the surface of a rapidly rotating grindstone.

For the best or most eflicient action of such a stone it is necessary that its surface be kept true so that all points on the surface of the stone lying in the same plane perpendicular to the axis shall represent a true circle. More definitely stated in order to keep the stone in proper condition it is necessary to give it frequent attention and redress it, therefore, my primary object is to provide a means whereby the operator may true the stone accurately and quickly.

One of the specific purposes, therefore, in carrying out the foregoing object is to provide a power means for carrying and controlling the truing tool or bur as it is commonly called that will move in a definite right line in a plane coinciding with or parallel to the axis of the stone or so that there. shall be no possibility for the bur to sag or shift under the action of the surface of the stone. Another object of the invention is to provide improved means for controlling the action of that type of bur that is calculated to act upon the surface of the stone in both a forward as well as a backward movement. A still further object is to provide power means adapted to be actuated automatically or semi-automatically as may be deemed best at any particular time for controlling the movement of the bur toward and from the stone, such means providing facilities for quickly actuating the bur in either direction. y

Vhereas in the most skilful and hence efiicient dressing of a large grindstone it is important to inspect the bur frequently as after each cut and for the bur to be renewed when its condition demands it, it is highly Specification of Letters Patent.

Patented June 4, i918.

Application filed March 23, 1918. Serial 110.2%,306.

important that means be provided for such easy and ready inspection and renewal or interchange of the bur, and this is another object realized by my improvement.

With the foregoing and other objects in view the invention consists in the arrangement and combination of parts hereinafter described and claimed, and while the invention is not restricted to the exact details of construction disclosed or suggested herein, still for the purpose of illustrating a practical embodiment thereof reference is had to the accompanying drawings, in which like reference characters designate the same parts in the several views, and in which-- Figure 1 is a plan view of my improve ment with the bur in position in contact with the face of the stone and about to make a cutting reciprocation across the face of the stone or toward the left as shown.

Fig. 2 is a vertical longitudinal section of the main carriage and motor therefor, the auxiliary carriage being shown in cross section. 7

Fig. 3 is a vertical transverse section on the line 3-3 of Fig. 2 showing the auxiliary motor and associated bur controlling means mainly in longitudinal section.

Fig. 4 is a vertical transverse section on the line 4.4 of Fig. 2; and

Fig. 5 is a horizontal sectional detail of a suitable type of 4-way valve such as I use in connection with either of the motors.

My invention in its preferred form comprises a rigidbase having a trough-shaped body 10 open at one end and having a girt 11 extending across the other end. For convenience of description these ends will be referredto hereinafter as front and rear,

the front end having the girt and arranged at the right hand end of the machine as the operator faces the work. The base 10 may also include any suitable end brackets 12 and 13 for securing it in rigid position. The upper edges of the base 10 are provided with undercut rails 14 and 15 which constitute guideways.

At 16 I indicate as a whole a main power carriage supported upon the base 10 and guided for reciprocations forward andrearward by means of undercut flanges 17 and 18 cooperating with the guideways 14 and.

15 respectively. The length of the carriage is substantially the same as that of the base and is sufiiciently longer than the. travel of the carriage to insure that an ample portion of the carriage will always have direct and intimate cooperation with the rigid base whereby the carriage will be confined in its movements strictly to reciprocations in' a horizontal plane making it impossible for the carriage or a ny part thereof to tilt, twist, sag or otherwise depart from said plane. The primary purpose of this ca'u'iage is to support and carry the bur 20 which nay be of any suitable or approved design or construction, the same, however, being supported for rotation upon a spindle 21 parallel to the direction of movement of the carriage. Any suitable means may be provided to support the bur upon the carriage, but attention is called particularly at this time to the means for reciprocating the carriage along the base. 22 indicates a strong rigid metal bar provided preferably with a coating or shell of brass thereon shown at 23. The front end of this rod is anchored by means of adjustable locking nuts 24 to the .girt 11, the rod extending thence rearward substantially coaxial of the curvature of the base 10. To the rear end of the rod is fixed a piston 25, the piston being locked thereon by means of a nut 26, or its equivalent, and thus the piston is held in stationary position. The main power motor includes also a cylinder 27 surrounding and cooperating with the piston. The, cylinder is fixed in any suitable manner to the carriage l6 and constitutes a part thereof. As indicated the carriage comprises three main parts 28, which may be termed the valve section and front and rear sections 29 and 30 respectively which may be termed port sections. The ends of the cylinder are preferably provided with right and left hand threads. respectively whereby they are secured in the respective port sections as shownbest in Fig. 2. The port sections are secured to the valve section 28 by any suitable means such for example as cap bolts 31. The carriage may be reciprocatcd in either direction by any suitable power fluid such as water, compressed air,'or steam, although in the usual practice of these machines water is commonly used. The power fluid is admitted in alternation into the opposite ends of the cylinder for coiiperation with the stationary piston. The means I provide to accomplish this action includes a 4-way valve 32 shown journaled in the upper portion of the valve section 28 of the carriage and preferably adjacent to the front end thereof. The valve is mounted for rotation around a vertical axis, the stem 33 thereof being journaled in a cap 34 or packing gland fixed to the top of the section 28. The body of the valve is provided with inlet and ex haust ports 35 and 36 respectively and'also front and rear ports 37 and 38 communicating respectively with ports 39 and 40 formed in the respective port sections of the carria e and so communicating with the front an rear ends of the cylinder. The valve as shown best in Fig. 5 is provided with ports 41 and 42, the port '41 in one position of the valve bringing the ports 35 and 38 into communication whereby the ower fluid is admitted into the rear end of the cylinder, while the port 42 brings the ports 36 and 37 into communication effecting an exhaust from the front end of the cylinder. This is the position of the valve corresponding to the illustrations in Figs. 1 and 2. When, however, the valve is given a quarter rotation by any convenient means the efl'ect of the inlet and exhaust ports is reversed, or the port 41 will communicate with the ports 36 and 38 to exhaust from the rear end of the cylinder while the port 42 will establish tive length of the rod 22 and hence the posi-.

tion of the piston for this purpose being determined by the adjustment of the nuts 24. On the return movement the limiting stop consists of a screw 44 fixed adjustably in the center of a cap or plug 45, the screw being adapted to impinge against the rear end of the rod 22. The provision'of the plug 45 serves to constitute a closure for the back end of the carriage. The intermediate portion of the rod 22 has aslidable fit in' a stuffing box 46 adjacent to the boss. 43 in the port section 29 of the carriage. Since the carriage is mounted for direct reciprocation and support upon the rigid base 10 through the interlocking or engagin guideways 14, 15, 17 and 18 nostraln is rought upon the rod tending to bend or distort it and so I have little difliculty in maintaining a perfectly fluid tight closure at the stufling box 46. It is to be noted in this connection also that the piston has its primary support in the cylinder and hence the rod is relieved from this function.

For hand manipulation or control of the valve 32 and hence the control of the reciprocations of the cylinder of the carriage, I fix to the upper end of the stem 33 a segment 47 of relatively short radius, and meshing with the teeth of this segment 47 is a larger segment 48 journaled for oscillation upon a stud 49 shown as fixed to the top of theport section 29. A lever 50 having a handle 51 at its rear end is journaled on a horizontal pivot 52 upon the segment 48 while a spring 53 of any suitable nature acts upon the front end of the lever to hold it down normally against the front end of the segment 48 or with the handle end 51 spaced above the plane of the segment 47. The connection beapse tween the lever and the segment 48 is such that when the lever is actuated so as to move it in a horizontal plane the segment 48 will be correspondingly moved around its ivot or stud 49 thereby rotatin the valve. s indicated best in Fig. 1- tfie rotation of the lever and segment 48 through approximately 60 degrees will efiect the desired quarter rotation of the valve. When the lever 5Q is manipulated by hand the operator grasping the handle 51 may obviously swing the segment 48 in either direction, and if necessary to lift the front end of the lever he will depress the handle end thereof against the force of the spring 53, as will more fully appear later.

Attention is now called to the preferred means for supporting and manipulating the bur 20. The pivot 21 is shown supported in the fork or yoke 54 having a rigid shank 55 adjustably fitted and locked in a groove or seat 56 formed in an auxiliary carriage 57 mounted upon and reciprocatable transversely upon the port section 29 of the main carriage. This auxiliary carriage 57 has dovetailed connection with the part 29 by means of the two undercut guides 58 and 59 shown best in Fig. 2. A-tapered shim 60 is located between the body of the carriage 57 and the rail or guide 59 to make proper fit and to take 11 wear for these parts.

As shown 1n Fig. 3 the under surface or edge of the shank 55 is provided with a series of notches 61 into any one of which the key 62 is adapted to project, said key being fixed in the member 57 beneath the shank. This key constitutes a positive means to prevent endwise movement of the shank and bur supported thereby with respect to the groove 56 and auxiliary carriage 57. The shank is held in place by any suitable clamping means such for example as a pair of plates 63 held in place by bolts 64. This ad uStment through the key and notches is for the purpose of providing an approximate effective length for the shank according to the reduction of diameter of the stone due to continued .use or wear. Ordinarily a stone for example that is 54 inches in diameter when new may be worn or dressed down to about 42 inches and still be serviceable- As to the normal adjustment, however, or control of the depth of the cut of the bur when truing or dressing the stone, it is effected 'by means of a hand operated screw 65 having bearing in a lug 66 adjacent to the operator on the right side of the auxiliary carriage and tapped through a lug or nut 67 fixed in or secured upon the right side of the carriage 57, the end of the screw being adapted to abut against a fixed stop or lug 68 on the remote side of the car riage from the operator. In other words the position of the screw in the nut 67 will determine the extent of possible movement of the burtoward the axis of the stone, and so larger segment 77 pivoted at 78. The seg-' while the work of dressing the stone progresses the operator at the handle 69 will increase the length of the stroke of the tool toward the stone without changing the adjustment through the shank as above described, but after the stone is worn down materially adresetting of the bur shank will be resorte to.

As a suitable and practical means for automatic or motor operated means for controlling the movements of the bur I show an auxiliary motor comprising a cylinder 70 fixed to the port section 29 of the main carriage. This 0 linder has at one end a removable plug 1 whileat its other end it is fitted with a stufiing box 72 through which the rod 73 of the piston 74 reciprocates. The other end of the piston rod 1s fixed to the auxiliary carriage 57. At any convenient place, as for instance in the bottom, the cylinder structure is fitted with a 4-wa valve 7 5 preferably of the same type as a ready described in detail and having fixed to its stem a segment 76 meshing with a slightly ment 77 carries a hand operated lever 79 mounted on a pivot 80, the axis of which is erpendicular to the axis of the stud or boss 8 or horizontal as shown in the present instance, the axis of the valve 75 being vertical. The valve ports communicate through ports 81 and 82 with the ends of the cylinder 7 0 in alternation, the pressure fluid being communicated through the valve 75 from the same source as that for the main motor or any other convenient source. The lever 79 is provided with a spring 83 serving to hold the end thereof remote from the operator in an upward position or toward the cylinder 70. Obviously the operator grasping the handle 84 may swing the lever and segment 77 around the axis of the stud 78 for reversing the position of the valve 75 and hence the direction of movement of the piston 74 and a parts controlled thereby. When the valve is in position to admit the power fluid between the plug 71 and the piston 74 said power fluid acts automatically to force and hold the bur 20 against the stone or as near to the stone as will be permitted by the screw 65.

Having thus set forth most of the mechanical features I will now describe the c cle of operation in ordinary practice.

tarting with the machine with the parts in position shown in Fig. 1, power fluid, such as water under pressure, will be understood to be admitted through the valve 32 into the rear end of the cylinder 27 or so as to act against the piston 25 and the plug 45 to cause the traverse of the main carriage rearward causing the bur 20 to ass across the face of the stone. The stone eing operated at high speed will insure the desired action 0 the bur in truing or resharpening the cylindrical face of the stone. For the best results it is desired that the bur will cease its cutting operation and be withdrawn from the stone at about the moment that the center of the bur registers with the rear edge or face of the stone. During this movement of the carriage the lever 79 and segment 77 will occupy the position shown in Fig. 1 beneath the cylinder or with the short arm of the lever 79 in advance of the pivot 78, the valve being so positioned that the power fluid will be admitted through the ort 81 acting upon the piston to force t e bur against or toward the stone. Just before the bur reaches the desiredlimit of lateral movement, say an inch more or less, the shorter end of the lever 79 will impinge against an adjustable sto 85 fixed to the base 10 at the desired polnt to make it effective. The main carriage continuing in its movement carrying with it the auxihary motor and valve mechanism causes the partial turning of the segment 77 and valve 75 to reverse the action of the power fluid and s0 force the bur directly away from the stone. By this time the boss 43 will have struck against the piston positively stopping the movement of the main carria e rearward though up to this moment t e main power fluid has not been reversed. 86 indicates a finger adjustably mounted upon the left side of the auxiliary carriage 57.

The outer or free end of'the finger carries an anti-friction roller 87 which while the carriage is moving away from the stone as indicated in dotted lines in Fig. 1 is engaged in a fork 88 constituting the shorter end of the lever 50. The auxiliary motor being now functional to move its carriage away from the stone this engagement with the lever 50 causes the reversal of the valve 32 automatically, and so the power fluid is admitted between the piston and the port section 29 of the mam carriage whereby the carriage is returned to its original position, the auxiliary motor controlling lever occupying the position shown in dotted lines in the left of Fig. 1 during this movement and with its shorter end in 7 position to abut against another adjustable stop 85 whereby the auxiliary motor may be reversed automatically to force the bur again into engagement with the face of the stone. When the main carriage returns thus to its original position the precise oint at which it will be stopped, so contro n the relation of the bur to the right side 0 the stone, will be determined by the adjustment of the screw 44 shown plainly in, Fig. 2.

Now with the carriage returned to its starting point and with the auxiliary motor valve devices reversed to cause the power fluid to force the auxiliary carriage and bur to or toward the stone the finger 86 durthe face of the stone ing such movement will again be received in the fork 88 and automatically cause the vmain motor to be reversed. By proper adually initiating the rearward reciprocation of the main carriage and bur he may do so readily and easily b grasping the handle 51 forcing the same ownward toward the valve 32 and throwin the forked end 88 upward out of the pat of the fin er 86 so that while the auxiliary carriage 5 carries the said fin er toward the stone it will not act u on t e valve mechanism. Likewise and o viously the operator by grasping the handle 84 may hold the lever 79 in such osition as not to be automatically actuated y either of the steps 85 or 85'. Or if the both of the stops 85 and 85 out of range of operation when that type of bur is being used that is adapted to act both ways across instead of in only one direction as the above description contemtained in contact both the forward and rearward movements, the operator reversing the main motor by one hand while with the other he controls the screw 65. He, through the actuation of the lever 79 may cause the withdrawal of the bur from cutting position. p

When the machine is out of operation both levers 50 and 79 are turned to mid position thereby locking thepistons in whatever position they happen to be in at the time. With the use of water for the (power means the cylinders are'kept cool, an the construction of the main carriage serves to protect the cylinder 27 from the hot pul the vat below it as well as being protected from the ulp carried by the stone. The desi of t e attachment is peculiarly well a apted for certam types of grinders because of its compact construction or low ner already described. The grindstone being however, at all times plates. In other words the bur may be rewith the stone during p or steam in raeaeae operated continuously at high speed durin all of the usual operations, t is a matter great importance for the bur to be under both easy and Complete control of the 0 erator for various reasons such as the sa ety to his hands in inspecting or changing the bur, cleansing, cooling or oiling the same, and for the most eflicient as well as the most rapid truing or cutting operation of the bur thelpower device set forth herein is much more satisfactory than other means heretofore roposed for this purpose.

I c aim:

1. In an automatic grindstone dresser, the combination of a main carriage, means to reciprocate the carriage parallel to the face of the stone, a bur, a support for the bur movably mounted upon the main carriage, and automatic means to move said support and bur in a direction perpendicular to the direction of movement of the main carriage.

2. In an automatic grindstone dresser, the combination with a main carriage and means to reciprocate it parallel to the face of the stone, of a bur, rigid supporting means for the bur carried by the main carriage, and automatic means acting upon the bur and its supportin' means to move the same in opposite directions in alternation transverse to the direction of movement of the main carriage.

In an automatic grindstone dresser, the combination with a main carriage and means to reciprocate the same in directions parallel to the face of the stone, of a bur, an auxiliary carriage constituting a rigid support for the bur carried by the main car-- riage, power means actin upon. the auxilary carriage serving to old the bur in contact with the face of the stone, and means to automatically cause said power means to withdraw the bur therefrom when the main carriage reaches the end of a reciprocation.

4. In an automatic grindstone dresser, the combination of a main carriage, a motor acting upon the same and reciprocating it in a direction parallel to the face of the stone, at bur, an auxiliary carriage constituting a rigid support for the bur mounted upon the main carria e, an auxiliary motor acting upon the auxi iary carriage and bur to reciprocate the same transversely of the main carriage, and automatic controlling means for the motors serving to cause the reversal of each motor as a direct result of the action of the other motor.

5. In an automatic grindstone dresser, the combination of a main carriage, a fixed base supporting the same, a stop member connected to the base, a motor acting upon the main carriage to reciprocate it parallel to the face of the stone, reversing means for the motor to cause the automatic return of the main carriage after making one reciprocation, a bur, an auxiliary carriage constituting a support for the bur and mounted upon and movable across the main carriage in directions perpendicular to the direction of movement of the main carriage, an auxiliary motor acting upon the auxiliary car riage and bur and acting in one direction to hold the bur against the stone, controlling" devices for the auxiliary motor cooperating with said stop to automatically reverse the auxiliary motor and so Withdraw the bur from the stone at a predetermined time, and means actuated by the auxiliary motor in said withdrawing action to reverse the main motor.

6. The combination with a main carriage and means to reciprocate the same parallel to the face of the stone, of an auxiliary carriage mounted for reciprocation on the main carriage perpendicular to the direction of movement of the main carriage, a bur and rigid connections between the bur and the auxiliary carriage comprising a shank, the auxiliary carriage having a groove into which said shank projects, a positive key engaging both the shank and the bottom of the groove, and clamping means acting upon the shank to hold it in the groove and so hold the key in locking po'sltion.

7. In an automatic grindstone dresser, the combination of a reciprocating carriage, a relatively fixed support for the carriage, a fluid pressure motor acting upon the carriage to reciprocate it in both directions a1- ternately, and reversing means for the motor, said reversing means including a lever, an actuating member, means to hold the lever in position to be actuated by said member, and means to actuate the lever by hand to the exclusion of said actuating member,

8. In an automatic grindstone dresser, the combination of a stationary trou h-shaped base having a vertical strut extendm across one end and a pair of spaced paralle ide rails extending'from the strut end, a piston within the trough, a fixed rod secured at one end to the piston and at the other end to said strut, a carriage mounted on said rails for reciprocations to and fro along the base. said carriageincluding a cylinder embracing and cooperatin with semi piston, means to admit power fluid into the opposite ends of the cylinder in alternation to act against said piston and cause the several reciprocations of the carriage, means to reverse said fluid pressure means either automatically or by hand, and a dressing tool carried by said carriage.

FRED E. RILEY. 

